From 38efd9d1bca8e85fff0e591a829955580303e0b0 Mon Sep 17 00:00:00 2001
From: Zebediah Figura <z.figura12@gmail.com>
Date: Thu, 21 Nov 2019 10:58:02 -0600
Subject: [PATCH] ntdll-x86_64_SegDs: Add patch.

---
 ...Ds-to-be-identical-to-SegSs-on-x86_6.patch | 45 +++++++++++++++++++
 patches/ntdll-x86_64_SegDs/definition         |  1 +
 patches/patchinstall.sh                       | 19 ++++++++
 3 files changed, 65 insertions(+)
 create mode 100644 patches/ntdll-x86_64_SegDs/0001-ntdll-Report-SegDs-to-be-identical-to-SegSs-on-x86_6.patch
 create mode 100644 patches/ntdll-x86_64_SegDs/definition

diff --git a/patches/ntdll-x86_64_SegDs/0001-ntdll-Report-SegDs-to-be-identical-to-SegSs-on-x86_6.patch b/patches/ntdll-x86_64_SegDs/0001-ntdll-Report-SegDs-to-be-identical-to-SegSs-on-x86_6.patch
new file mode 100644
index 00000000..455a3be4
--- /dev/null
+++ b/patches/ntdll-x86_64_SegDs/0001-ntdll-Report-SegDs-to-be-identical-to-SegSs-on-x86_6.patch
@@ -0,0 +1,45 @@
+From 1178a02719088e81b2e5b35074b4559f60d8a5b1 Mon Sep 17 00:00:00 2001
+From: Zebediah Figura <z.figura12@gmail.com>
+Date: Thu, 21 Nov 2019 10:44:42 -0600
+Subject: [PATCH] ntdll: Report SegDs to be identical to SegSs on x86_64.
+
+Based on a patch by David Torok.
+
+Wine-Bug: https://bugs.winehq.org/show_bug.cgi?id=47970
+Signed-off-by: Zebediah Figura <z.figura12@gmail.com>
+---
+ dlls/ntdll/signal_x86_64.c | 11 ++++++-----
+ 1 file changed, 6 insertions(+), 5 deletions(-)
+
+diff --git a/dlls/ntdll/signal_x86_64.c b/dlls/ntdll/signal_x86_64.c
+index c372f65b34b..a1797811da3 100644
+--- a/dlls/ntdll/signal_x86_64.c
++++ b/dlls/ntdll/signal_x86_64.c
+@@ -1699,11 +1699,6 @@ static void save_context( CONTEXT *context, const ucontext_t *sigcontext )
+     context->SegFs  = FS_sig(sigcontext);
+     context->SegGs  = GS_sig(sigcontext);
+     context->EFlags = EFL_sig(sigcontext);
+-#ifdef DS_sig
+-    context->SegDs  = DS_sig(sigcontext);
+-#else
+-    __asm__("movw %%ds,%0" : "=m" (context->SegDs));
+-#endif
+ #ifdef ES_sig
+     context->SegEs  = ES_sig(sigcontext);
+ #else
+@@ -1714,6 +1709,12 @@ static void save_context( CONTEXT *context, const ucontext_t *sigcontext )
+ #else
+     __asm__("movw %%ss,%0" : "=m" (context->SegSs));
+ #endif
++   /* Legends of Runeterra depends on having SegDs == SegSs in an exception
++    * handler. Testing shows that Windows returns fixed values from
++    * RtlCaptureContext() and NtGetContextThread() for at least %ds and %es,
++    * regardless of their actual values, and never sets them in
++    * NtSetContextThread(). */
++    context->SegDs  = context->SegSs;
+     context->Dr0    = amd64_thread_data()->dr0;
+     context->Dr1    = amd64_thread_data()->dr1;
+     context->Dr2    = amd64_thread_data()->dr2;
+-- 
+2.23.0
+
diff --git a/patches/ntdll-x86_64_SegDs/definition b/patches/ntdll-x86_64_SegDs/definition
new file mode 100644
index 00000000..aa6491a7
--- /dev/null
+++ b/patches/ntdll-x86_64_SegDs/definition
@@ -0,0 +1 @@
+Fixes: [47970] Legends of Runeterra crashes at launch
diff --git a/patches/patchinstall.sh b/patches/patchinstall.sh
index 8e295a8a..cd8ce0c2 100755
--- a/patches/patchinstall.sh
+++ b/patches/patchinstall.sh
@@ -228,6 +228,7 @@ patch_enable_all ()
 	enable_ntdll_aarch_TEB="$1"
 	enable_ntdll_ext4_case_folder="$1"
 	enable_ntdll_set_full_cpu_context="$1"
+	enable_ntdll_x86_64_SegDs="$1"
 	enable_ntoskrnl_Stubs="$1"
 	enable_nvapi_Stub_DLL="$1"
 	enable_nvcuda_CUDA_Support="$1"
@@ -807,6 +808,9 @@ patch_enable ()
 		ntdll-set_full_cpu_context)
 			enable_ntdll_set_full_cpu_context="$2"
 			;;
+		ntdll-x86_64_SegDs)
+			enable_ntdll_x86_64_SegDs="$2"
+			;;
 		ntoskrnl-Stubs)
 			enable_ntoskrnl_Stubs="$2"
 			;;
@@ -5173,6 +5177,21 @@ if test "$enable_ntdll_set_full_cpu_context" -eq 1; then
 	) >> "$patchlist"
 fi
 
+# Patchset ntdll-x86_64_SegDs
+# |
+# | This patchset fixes the following Wine bugs:
+# |   *	[#47970] Legends of Runeterra crashes at launch
+# |
+# | Modified files:
+# |   *	dlls/ntdll/signal_x86_64.c
+# |
+if test "$enable_ntdll_x86_64_SegDs" -eq 1; then
+	patch_apply ntdll-x86_64_SegDs/0001-ntdll-Report-SegDs-to-be-identical-to-SegSs-on-x86_6.patch
+	(
+		printf '%s\n' '+    { "Zebediah Figura", "ntdll: Report SegDs to be identical to SegSs on x86_64.", 1 },';
+	) >> "$patchlist"
+fi
+
 # Patchset ntoskrnl-Stubs
 # |
 # | Modified files: